Mueller publicly disputed the BuzzFeed report. Here’s why it’s a such rare move for a prosecutor.

BuzzFeed broke what seemed to be a bombshell story late on Thursday, alleging that special counsel Robert S. Mueller III’s team had collected evidence that proved President Trump broke the law.

If the report had been accurate, it would have been the “smoking gun” denied by Trump’s supporters and hoped for by his opponents.

The next morning, reporters frantically tried to fact-check BuzzFeed’s details, which were attributed to two anonymous sources. Hours passed without another outlet substantiating the report. Then Mueller’s team came out and said the details alleged by BuzzFeed’s Jason Leopold and Anthony Cormier about the special counsel’s investigation into Russian election interference were not accurate.

Mueller’s office released a rare public statement Friday afternoon — the first directly discussing evidence collected during its Russia investigation. Carefully and opaquely crafted, it never denied BuzzFeed’s story in full, but it made the case that the report either overstated or mischaracterized the evidence collected.

Peter Carr, a spokesman for Mueller, said: “BuzzFeed’s description of specific statements to the special counsel’s office, and characterization of documents and testimony obtained by this office, regarding Michael Cohen’s congressional testimony are not accurate.”

Under the federal rules of criminal procedure, evidence that comes before a grand jury is confidential. Barring few exceptions, federal prosecutors are not allowed to reveal specifics about the testimony or documents presented.

These rules apply only to grand jury secrecy and do not cover the investigation as a whole, he explained. A prosecutor can inform the public about general goals or themes of an investigation. While there is no inherent limitation on prosecutors commenting on pending cases, it is nevertheless rare for one to do so.

“Mueller’s statement didn’t implicate the grand jury. It did not say what evidence was or was not presented, and it only vaguely referred to the investigation,” Weisberg said. It did not mention which BuzzFeed details were false, but it still signaled at a minimum that the website did not have the facts straight.

A person could count the times Mueller has publicly commented on the investigation with one hand. After dozens of stories, some that seemed to stray from the facts, he remained silent. Why, then, did Mueller opt to issue a statement on Friday?

Legal experts posited Mueller would have preferred to say nothing, but he feared specifics of the BuzzFeed story would be imputed to the investigation.

According to BuzzFeed’s report, prosecutors had evidence that Trump directed his former attorney, Michael Cohen, to lie to Congress, an action that could meet the definition of the “high crime or misdemeanor” needed to initiate impeachment proceedings. It could also support independent felony charges.

Thursday was not the first time BuzzFeed opted to publish a controversial report.

In January 2017, the outlet circulated the now well-known Steele dossier, a 35-page collection of memos with unverified allegations about Trump and Russian interference in the 2016 presidential election.

In both the case of the dossier and in last week’s story, Trump called the website’s reporting “fake news.” Both times, BuzzFeed editor Ben Smith stood behind the website’s reporting.

“We stand by our reporting and the sources who informed it,” Smith said Friday, urging Mueller to clarify which statements his office disputes.

It is unlikely Smith will receive a response, Alan Charles Raul, a lawyer who served in the Reagan White House and both Bush administrations, told The Post.

“I’m sure [Mueller] won’t start making a habit of commenting on rumors though, and he shouldn’t,” Raul said.

He said that the statement from the special counsel’s office is “a confirmation of Mueller’s fairness” and “a recognition of his enormous responsibility.”

Mueller evidently decided he could not allow an erroneous but devastating report to go uncorrected, said Raul, who also helped found the group Checks and Balances. The group is dedicated to speaking up for the rule of law, but Raul addressed the recent Mueller issue in a personal capacity only.

“The rumor he debunked would have quickly snowballed into a sensational accusation leading to an irresistible impulse for impeachment hearings,” he added. “Given the stakes if Mueller hadn’t set the record straight, he took the responsible course to shut the issue down.”